Preface - Ous-research.no

Plastic and reconstructive surgery
3. Microcirculation and wound healing:
To resemble a clinical situation, we are using animals with
skin structure and function similar to the human skin. Pig
skin has many similarities to human skin, including histological
appearance and wound healing ability. We are using
Norwegian pigs (Norsk landsvin) with weight between 25
and 30 kg in our studies. Microcirculation and histological
measurements are performed to evaluate the effect of different
reconstructive procedures or other interventions on
wound healing. To investigate microcirculation and wound
healing in an isolated setting, we use rat models as described
below.
4. Experimental perforator flaps and other rat models
Dissection of the perforator flaps preserves the muscle
and minimizes the donor site morbidity. Nevertheless,
the method may have undesirable effects on the muscle
because of damage of its innervation, blood supply or by
direct injury when dissecting the perforator. This damage
can be reduced by including a minimum number of perforators.
However, a reduced number of perforators may
be detrimental to the flap viability and wound strength.
To study the effect of different numbers of perforators in a
lipocutaneous flap we are using Wistar rats where two symmetrical
abdominal lipocutaneous flaps are raised around
the midline. On one side all major perforators of the flap are
left intact and on the other side only the largest perforator is
retained within the flap. After dissection, the flaps are fixed
to the original position by a continuous suture. Microcirculation,
flap viability, wound strength and histological changes
are measured preoperatively and during the first week after
the operation.
To continue improvements in both a clinical and scientific
setting research using animal models is important. The
groin flap based on the superficial inferior epigastric artery
(SIEA) is well described. However, as shown in our previous
research there are problems with autocannibalism. In addition,
postoperative flap monitoring is difficult when the flap
is translocated to the abdominal side of the animal. Some
studies have addressed these problems by transferring the
flap to the dorsum of the rat. However, in these experiments
the femoral vessels were ligated, with danger of an ischemic
limb and possible tissue necrosis. The ischemic tissue may
release factors that affect the microcirculation of the free
flap. We have established a new SIEA flap model in the rat
with good conditions for flap monitoring, without danger of
flap autocannibalisation and with preserved limb circulation
(fig 2). This model is used when performing studies on
microcirculation and histological changes where we want
to compare different interventions on the flap or the animal
over a longer period of time.
5. Microcirculation and reinnervation in human perforator
flaps.
The deep inferior epigastric artery perforator (DIEAP) flap
from the abdomen is one of the most suitable perforator
flaps used for breast reconstruction (fig 3 and 4). This
procedure has had a significant impact on the field of plastic
and reconstructive surgery, because of the high number of
women requiring breast reconstruction after cancer surgery.
Based on the experimental research and clinical experi-
Figure 3. The abdominal flap is transposed to the thorax and is
ready for revascularization.
Figure 2. Dissection of the groin flap (left). Transposistion of the
flap to the dorsum of the rat (right)
Figure 4. Preoperative markings on the patient (left), and after
breast reconstruction with DEIAP flap (right).
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